Pneumatic-despatch-tube system



(No Model.) 2 Sheets-Sheet 1. A. W. PBARSALL.

PNEUMATIG DESPATGH TUBE SYSTEM. No. 582,829. Patented May 18,1897.

(No Model.) 2 Sheets-Sheet 2'.

A. W. P-EARSALL. PNEUMATIC DBSPATGH TUBE SYSTEM.

No. 582,829. Patented May-18, 1897.

UNITED STATES PATENT OFFICE.

ALBERT W. PEARSALL, OF NElV YORK, N. Y., ASSIGNOR TO THE METEOR DESPATOH COMPANY, OF PORTLAND, MAINE.

SPECIFICATION forming part of Letters Patent No. 582,829, dated May 18, 1897.

Application filed January 9, 1896. Serial No. 574,898. (No model.)

To all whom it may concern.- is a plan view of a cashiers station. Fig. 4 Be it known that I, ALBERT WV. PEARsALL, is an end view of a cashiers station. Fig. of New York, county of New York, and State is a detail view of the regulating device hereof New York, have int ented new and useful inafter described. 5 Improvements in Pneumatic-DespatchTube Like letters of reference refer to like parts Systems, of which the following is a specilithroughout the several views. cation; and I hereby declare that the follow- From the cashiers station A there extends ing is a full, clear, and exact description of a line of tube B to the terminal 0, located at theinvention,whichwill enable others skilled the salesmans station D. At the cashiers I0 in the art to which it appertains to make and station there is provided a despatch-box E, use the same. having an openended collar E, through My invention relates to new and useful 1111- which the carrier is inserted into the deprovements in pneumatic-despatch-tube sysspatch-box to be sent to the salesm'ansstation tems in which pressure behind the carriers D. The collar E is partially closed at the 15 is used to despatch the same from one part top, upon the insertion of the carrier, by the of the system to the other, in distinction from cover E, secured to the lever E pivoted at vacuum systems in which carriers are drawn E between the lugs E secured to the outalong by the vacuum created in front thereof. side of the collar E, and said lever, to the My invention especially relates to a system rear of its pivot-pointE is provided with a 20 in which the air-pressure is started into circam-surface E and at its forward end is proculation upon the insertion of a carrier into vided with a finger-catch E and a projection the tubes, as normally there is no circulation E At the lower end of the despatch-box E, of pressure through said system. By such an and in communication therewith by means arrangement there is a great saving of power of the narrow passage F, is a chamber F, 25 over systems in which the circuit is always closed to the atmosphere by a flexible diaopen and the pressure constantly passing phragm F secured in place by a metallic through the tubes, -whether the carriers are rim F To the center of this flexible diabeing transmitted or not. phragm is an arm F to which the vertical One object of my invention is to produce lever F is pivoted at F, and said lever ex- 0 a system in which pressure is introduced into tends upwardly through the flange E of the p the transmitting-tubes of the system upon collar E, and near its upper end is provided the insertion of a carrier. with a hub F journaled on the pin F Another object is to produce a system in mounted in the lugs F secured to the side which, upon the arrival of the carrier at its of the despatch-box E, and at its upper end 5 destination, the pressure which has driven said lever has a dog F which is adapted, as said carrier from the starting-point to its deswill be hereinafter explained, to engage with tination is cut off upon the discharge of said the projection E of the lever E and hold the carrier. said lever down and the cover closed when a I These and other objects are accomplished carrier is being transmitted through the sy 9o 40 by the mechanism hereinafter described, and tem. On the same side of the despatch-box shown in the drawings. E as the lever F there is a lug G, to which My invention consists of certain novel feais secured a fiat spring G by a suitable screw tures hereinafter described, and particularly G and said spring extends upwardly through pointed out in the claims. a suitable bearing in the base-plate E and 9 5 5 In the accompanying drawings, which illusits upper end bears against the dog F on the trate a construction embodying my invenupper end of the lever F and tends to hold tion, Figure 1 is a side elevation of a pneusaid dog F outward, and the lower end, to maticdespatch-tube system showing the which is secured the arm F, with the flexible salesmens and cashiers stations, with cerdiaphragm F inward, as shown in full lines, [00 5o tain parts of said stations in section. Fig. 2 Fig. 1.

is a detail view hereinafter described. Fig. 3 H represents a regulating device, (shown in detail in Fig. 0,) and it consists of a lever H, pivoted in the lug I1 extending from the side of the despatch-box E, (see Fig. 5,) and through the short end II of said lever there extends a thumb-screw H with its inner end bearing against the side of the despatch-box, while the end II bears against the flat spring G. In order to increase the tension of said spring G against the upper end of the lever F and create a greater inward pressure on the flexible diaphragm 11 the thumb-screw H is screwed up tightly, thus bringing out the short end II and moving the long end II inwardly against the flat spring G, and thus increasing the pressure of the spring against the upper end of the lever F or if it is desired to decrease the pressure of said spring on said lever the thumb-screw is unscrewed, thereby moving the short end 11 inwardly and the long end H outwardly, thereby reducing the pressure on said fiat spring G of said long end H and the pressure of the spring G against the upper end of the lever F for a purpose to be hereinafter described. In order to hold the regulating device II in its adjusting position, a locking-disk II is provided, which is adapted to be screwed down on the lever II, as shown in Fig. 5, and thus holds the thumb-screw in its adjusted position.

\Vithin the despateh-box E is a valve .I, pivoted at J and normally across the opening of the passage J into the despateh-box E. The said passage J 2 communicates at its other end with an auxiliary reservoir K, at the lower end of which the lever K is pivoted at K and to said lever there is secured the valve K which normally closes the opening of the passage J into the auxiliary reservoir K. The upper end of the lever K is provided with a slot K", and in said slot there is located a pin K on the end of the rod K, which passes through a boss K in the flat side of the auxiliary reservoir K, and around said rod K there is a spring K resting at its opposite ends againstthe boss K and head K of the said rod, and the tension of said spring is exerted to hold said rod outwardly, as shown in full lines, Fig. l, and thus to hold the valve K closed and the lever E and cover E in their open positions, as shown in full lines, Fig. 1. The said auxiliary reservoir K receives its air-supply through the pipe L, which is in communication with an air-reservoir L. The tube B, connected to the bottom of the despatch-box E, extends to the terminal 0 at the salesmans station D. The said terminal 0 consists of flat sides 0", with an outercurved guiding-plate C and an inner curved guidingplate C and between said plates 0 and (J the carrier passes when received from the tube B, and at the extreme inner end of said guiding-plate C guide-rods C are secured, and this arrangement permits the pressure passing around between the inner and outer plates 0 and C to pass between and around the rods 0 to the outlet-tube M, but at the same time the said guide-rods C guide the carrier to the outlet of the terminal, which is closed by the valve C. This valve consists of two leaves C and 0 joined together by a suitable connecting-rod C and said Valve C is pivoted to the terminal at C", the area of the leaf (J exposed to the pressure in the system being greater than the area of theleaf C exposed to the same pressure. The said valve (1 is held in this closed position, as shown in full lines, Fig. 1, by the pressure in the system, and the momentum of the discharged carrier is suflicient to open the valve C to permit the discharge of the carrier, and instantly upon the said discharge the pressure on the larger leaf 0 closes the valve and holds it in a closed position, as shown.

The valve (J is substantially of a construction and operates substantially the same as the pressure valve shown, described, and claimed in Letters Patent No. 527,073, dated October 0, 1894, and granted to the Meteor Despateh Company, of Maine, as my assignce.

Vhen it is desired to send a carrier from the eashiers station A to the salesmans station D, the operator places a carrier through the collar E into the (lespatch-box E and then pulls down the leve1'E ,and in said movement of the lever and the closing of the cover E the cam-face operates against the head K" of the rod K and pushes said rod inwardly against the tension of the spring K so that the pin K acts on the lever K and moves said lever, with the valve K secured thereto, backward to the position shown in dotted lines, Fig. 1, and thus opens the passage J to the air-pressure in the auxiliary reservoir K. The air passes through the passage J into the despatch-box E and raises said valve J upwardly to the position shown in dotted lines, Fig. 1, and thus closes and prevents any escape of the air up through the collar E, and the pressure acting 011 the carrier drives the same througlrthe tube B to the terminal 0, where it is discharged as above described. If it were not for this valve .I, as the pressure passed into the despatch'box E it would act on the under side of the cover E and create such a friction between the projection E on the lever E and the dog F" as to prevent the proper working of the lever E lever F", and diaphragm F By means of the valve J there is practically no pressure on the under side of the cover E and said cover acts more as a rest for the lever E than to prevent the escape of the air. Immediately upon the passage of the air into the despatchbox E the said pressure acts on the flexible diaphragm F and moves the same outwardly with the lever F, the upper end of which moves inwardly, and the deg F" engages with the projection E on the lever E and holds said lever down and said cover in a closed position, as shown in dotted lines, Fig. 1.

After the carrier has been inserted into the despatch-box and the lid closed it is driven through the system, as above described, and the carrier on reaching the terminal 0 opens the valve and is discharged; but in the opening of the said valve to allow the dis charge of the carrier a large opening is provided forthe escape of the pressure in the system, whereby the back pressure is immediately affected and reduced throughout the line, so that the diaphragm F and lever F owing to the reduction of pressure in the system,return to their normal positions,as shown in full lines, Fig. 1, and at the same time the lever E is released from engagement with the dog F and the lever F and immediately the lever and the cover fly upward and uncover the opening to the despatch-box E, as the tendency of the rod K owing to the tension of the spring K is to hold the lever E in a raised position. From this it will be seen that immediately upon the discharge of the carrier the back pressure in the line is so reduced as to permit the automatic release of the lever E from engagement with the lever F and as said leverrises, owing to the movement of the rod K against the cam-face E of said lever, the valve K is closed by reason of the tension of the spring K on the rod K moving said rod outwardly and raising the lever E as described, so that in the one movement, owing to the tension of the spring K the rod K raises the lever E and cover E", and at the same time closes the valve K and thus shuts off the pressure from the system. Upon the closing of the valve K the pressure being out off from the despatch-box E through the passage J the valve J drops to its normal position, as shown in full lines, Fig. 1, and the line is open and ready forinsertion and transmission of another carrier from the salesman to the cashier, and the op eration is repeated, as above described.

The pressure throughout the tube varies in different systems, sometimes being ten-ounces to the square inch and sometimes fifteen ounces to the square inch. Therefore the pressure on the flexible diaphragm F varies; but at all times it is necessary to have sufficient pressure on the flexible diaphragm F to hold the dog F of the lever F in engagementwith the projection E of the lever E upon the insertion and transmission of a carrier, the lever being moved by the hand, but the action of the pressure is so quick that the engagement of the dog F with the projection E is almost instantaneous with the insertion of a carrier, the downward movement of the lever, and closing of the cover, and in order to have this immediate action it is necessary that there should always be sufficient pressure in the system to act on the diaphragm F and overcome the tension of the spring G, so as to cause the immediate engagement of the dog F with the projection E of the lever E In order to regulate the proper amount of pressure on the diaphragm F I have provided the regulating device H, previously referred to. If the internal pressure in the system 011 the diaphragm F is high, the thumb-screw H would be screwed inwardly,

so as to move the end H inwardly against the spring G and thereby increase the tension of the spring G against the upper end of the lever F so as to counterbalance the high pressure in the system. When the pressure in the line is reduced by the delivery of a carrier at the terminal 0, the lever F will return to its normal position owing to the reduction of pressure in the system by the escape of pressure at the terminal and by the tension of the spring G against the upper end of the lever F thereby allowing the release of the lever E which in opening, by reason of the rod K, as above described, shuts oft the pressure from the line by the closing of the valve K this regulating device it will be obvious that if the pressure is high in the system the discharge of the carrier at the terminal 0 may not provide suflicient escape of the pressure in the line as to reduce the back pressure sufficiently to allow the return of the flexible diaphragm F and the lever F to their normal positions in order to release the lever E from engagement with the dog F on said lever F On the other hand, if the pressure in the system is low, it is obvious that the tension of the spring G against the upper end of the lever F must be reduced, so that the tension of said spring acting on the lever F and diaphragm F would not exert too much pressure, so as to hold said diaphragm inwardly, as shown in full lines, Fig. 1, against the pressure in the system and at the same time to keep the dog F from engagement with the projection E on the cover E In such cases of low pressure the thumb-screw II is screwed outwardly, so as to allow the end H to move outwardly and thus reduce the tension of the spring G against the upper end of the lever From the above it will be seen that the regulating device H is for the purpose of adjusting the tension of the spring G on the lever F and the diaphragm F to meet the varying pressures in the syste1n-that is, when the pressure in the system is high the regulating device increases the tension of the spring G on the lever F and diaphragm F but when the'pressure in the system is low the regulating device II reduces the tension of the spring G on the lever F and diaphragm F so that in all cases said regulating device adjusts the tension of the spring G on the lever F and diaphragm F so that upon the discharge of the carrier from the terminal 0 the escape of pressure from the system through the opening caused by the opening of the valve 0 is sufficient to reduce the back pressure in the system to such an extent as to allow the lever F owing to the pressure of the spring G, to move the diaphragm F inwardly, as shown in full lines, Fig. 1, and thereby to permit the release of the dog F and the upward movement of the lever E To the end of the short tube M, I have se- In the absence of cured a windgate M, which consists of an outer cylinder M provided with an opening M and within said cylinder M there is arranged another cylinder M, provided with an opening M adapted to register with the opening M of the outer cylinder M and secured to the bottom of said inner cylinder M is a shaft M, by means of which the inner cylinder can be revolved to adjust the opening M in relation to the opening M of the outer cylinder M The object of this windgate on the end of the line is for the purpose of regulating the amount of back pressure in the line, as such back pressure is necessary in the working of the system-that is, it is necessary to have sufficient back pressure in the despatch-box E to force the diaphragm F out, as shown in dotted lines, Fig. 1, upon the insertion of a carrier. Now if the tube M was freely open to the atmosphere there would not be enough back pressure in the despatchbox to hold the diaphragm F out and the lever E held down by engagement of the dog F with the projection E 011 said lever. Therefore said windgate is for the purpose of regulating the back pressure in the line so as to have the proper amount of back pressure in the system, and this will vary on different systems. For instance,if there was a long line less back pressure would be required than on ashort line. Consequently the inner cylinder M would be turned so as to register the openings h and M and allow an escape of the pressure in the line; but on short lines the openings M and M would not be brought into such full registration as on long lines, but the inner cylinder M would be turned so as to allow a smaller escape of pressure than on long lines, as in long lines there is a certain amount of friction, which of itself creates a certain amount of back pressure, so that for varying lines in order to regulate the amount of back pressure the inner cylinder M is adjusted to bring its opening M into proper relation with the opening M of the outer cylinder M and in long lines it is so adjusted as to allow a larger escape of air than in short lines.

From the above it will be seen that the wingate M is for the purpose of reducing or increasing the back pressure in the system sufliciently to admit of the proper operation of the lever F diaphragm F and dog F in relation to the lever E in addition to the back pressure exerted by the carriers, which, due to the varying loads which they may have, would not in itself be suiiicient to make the above-mentioned parts work with a sufficient degree of certainty. It is intended that sufiicient back pressure be exerted by the regulation of the windgate to hold the diaphragm F lever F and dog F in such position as to prevent the lever E when moved to the position shown in dotted lines, Fig. 1, from being released from engagement with the dog F even if there are no carriers in- .set forth the construction of my invention,

what I claim as new, and desire to secure by Letters Patent of the United States, is

1. In a pneumatie-despatch-tube system, a carrier-tramsmitting tube having an inlet and an outlet for the carriers, an air-inlet, a valve normally closing said air-inlet, mechanism for opening said valve, and a locking device connected with said tube and by the pressure of air therein being caused to engage with said valve-opening mechanism to hold said valve in an open position.

2. In a pneumatic-despatch-tube system, a carrier-transmitting tube having an inlet and an outlet for the carriers, an air-inlet, a valve normally closing said air-inlet, mechanism for opening said valve, a locking device connected with said tube and by the pressure of air therein being caused to engage with said valve-opening mechanism to hold said valve open, an air-outlet, and means for controlling the passage of air through said air-outlet.

3. In a pneumatic-despatch-tube system, a carrier-transmitting tube having an inlet and an outlet for carriers, an air-inlet, a valve normally closing said air-inlet, mechanism for opening said valve to permit the passage of air through said air-inlet, and a locking device connected with said transmitting-tube and operated by the pressure of air therein adapted to engage with said mechanism to hold said valve open until the pressure of air in the said transmitting-tube is reduced to such an extent as to cause said locking device to release said mechanism.

4. In a pneumatic-despatch-tube system, a carrier-transmitting tube having an inlet and an outlet for the carriers, an air-inlet, avalve normally closing said air-inlet, mechanism for opening said valve to permit the passage of air through said air-inlet, a locking device adapted to engage at one end with said mechanism for holding said valve open and connected at its other end to a flexible diaphragm exposed to the pressure in the said transmitting-tube admitted through said airinlet upon the operation of said mechanism, and means bearing on said locking device to cause the end connected to said diaphragm to exert a pressure on said diaphragm against the pressure in the said transmitting-tube.

5. In a pneumatic-despatch-tube system, a carrier-transmittin g tube having an inlet and an outlet for the carriers, an air-inlet, avalve normally closing said air-inlet, mechanism for troduced into the system. By this arrange- 1 opening said valve to permit the passage of air carrier-transmitting tube having an inlet and an outlet for the carriers, an air-inlet, a valve normally closing said air-inlet, mechanism for opening said valve to permit the passage of air through said air-inlet, a lockin g device adapted to engage With said mechanism for holding said Valve open and connected to a flexible diaphragm exposed to the pressure in the said transmitting-tube admitted through said air: inlet upon the operation of said mechanism, and means bearing on said locking device to cause said locking device to exert a pressure on said diaphragm against the pressure in the said transmitting-tube.

7. In a pneumatic-despatch-tube system, a carrier-transmittin g tube having an inlet and an outlet for the carriers, an air-inlet, a valve normally closing said air-inlet, mechanism for opening said valve to permit the passage of air through said air-inlet, a lockin g device adapted to engage with said mechanism for holding said valve open and connected to a flexible diaphragm exposed to the pressure in the said transmitting-tube admitted through said airinlet upon the operation of said mechanism, and adjustable means bearing on said locking device to cause said locking device to exert a pressure on said diaphragm against the pressure in the said transmitting-tube.

8. In a pneumatic-despatch-tube system, a carrier-transmitting tube having an inlet and an outlet for the carriers, an air-inlet, a valve normally closing said air-inlet, mechanism for opening said valve to permit the passage of air through said air-inlet, a lockin g device adapted to engage with said mechanism for holding said valve open and connected to a flexible diaphragm exposed to the pressure in the said transmitting-tube admitted through said airinlet upon the operation of said mechanism, means bearing on said lockin g device to cause said locking device to exert a pressure on said diaphragm against the pressure in the said transmitting-tube, an air-outlet, and means for controlling the escape of pressure through said outlet and thereby regulating the back pressure in the said transmitting-tube.

9. In a pneumatic-despatch-tube system, a carrier-transmitting tube having an inlet and an outlet for the carriers, an air-inlet, a valve normally closing said air-inlet,mechanism for opening said valve to permit the passage of air through said air-inlet, a locking deviceadapted to engage With said mechanism for holding said valve open and connected to a flexible diaphragm exposed to the pressure in the said transmitting-tube admitted through said airinlet upon the operation of said mechanism, adjustable means bearing on said locking device to cause said locking device to exert a pressure on said diaphragm against the pressure in the said transmitting-tube, an air-outlet, and means for controlling the escape of pressure through said outlet and thereby regulating the back pressure in the said transmitting-tube.

10. In a pneumatic-despatch-tube system, a carrier-transmitting tube having an inlet and an outlet for the carriers, an air-inlet, a valve normally closing said air-inlet, mechanism for opening said valve to permit the passage of air through said air-inlet, a locking device adapted to engage with said mechanism for holding said valve open and connected to a flexible diaphragm exposed to the pressure in the said transmitting-tube admitted through said airinlet upon the operation of said mechanism, adjustable means bearing on said lockin g device to cause said locking device to exert a pressure on said diaphragm against the pressure in the said transmitting-tube, an air-outlet, and adjustable means for controlling the escape of pressure through said outlet and thereby regulating the back pressure in the said transmitting-tube.

.11. In a pneumatic-despatch-tube system, a carrier-transmitting tube having an inlet and an outlet for the carriers, an air-inlet, a valve normally closing said air-inlet,mechanis1n for opening said valve to permit the passage of air through said air-inlet into the system, a lever having a dog at its upper end adapted to engage With said mechanism for holding said valve open and connected at its lower end to a flexible diaphragm exposed to the pressure in the said transmitting tube admitted through said air-inlet upon the operation of said mechanism, a spring bearing against the upper end of said lever to cause the lower end of said lever to exert a pressure on the diaphragm against the pressure in the said transmitting-tube, and means for regulating the pressure exerted on the upper end of said lever by said spring.

12. In apneumatic-despatch-tube system, a carrier-transmittin g tube having an inlet and an outlet for the carriers, an air-inlet, a valve normally closing said air-inlet,mechanism for opening said valve to permit the passage of air through said air-inlet, and a locking device adapted to engage with said mechanism for holding said valve open by the pressure in the said transmitting-tube admitted through said air-inlet upon the operation of said mechanism and adapted to be released from engagement With said mechanism upon the discharge of the carrier from the said outlet.

13. In a pneumatic-despatch-tube system,a carrier-transmitting tube having an inlet and an outlet for the carriers, an air-inlet, a valve normally closing said air-inlet,mechanism for opening said valve to permit the passage of air IIO to its normal position upon the discharge of the carrier from the said transmitting-tube.

In testimony whereof I have signed my name to this specification, in the presence of IS two subscribing Witnesses, on this 6th day of January, A. D. 1890.

ALBERT PEARSALL.

Witnesses:

EMMETT R. CLARKE, JAMES R. HAWKES. 

